I got a pretty good deal on closeout for a leather jacket online. Im 5'7 (maybe 5'8, i dont know) about 140lbs. I went to the only 3 dealers within a hr drive of me to try on jackets and they only had smalls, or large a* jackets or a bunch of leathers for chopper riders. I tried on the small and it was snug, it was killing me but I suppose it could be a little more loose. They only had 1 sz 40 left, and a few 38's. I ordered a 38 because I don't want it to be too loose and ill be riding with light clothes under for summer time. I can return it if its not the right size, but by the time it gets here in a week the 1 sz 40 they have left might be sold before I can exchange.
Do you think the 38 will fit well, or should I call and swap it with the 40 now?

 

You want your jacket to fit snug. If the jacket is to loose, the armor will move around and possibly not protect the body parts they were intended to protect. Once you start wearing the jacket, the leather will become softer and stretch (just a little bit).

 

I think the 38 should fit well if you are average build. If you work out a lot and have big shoulders/chest, maybe a 40 will be better.

But from you first post, I think you made the right choice.